Ex-Army Officer Here...
Blackshirt,
Spent almost 15 years in the military (Army) - 9 active and 6 reserve...
I agree (somewhat) with those that say don't join just to get away from something...although that IS a time-honored reason for joining the military through the ages

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A lot depends on what you are looking to get out of your experience. If you want to find out what you are made of, how far you can push yourself and gain valuable leadership skills (regardless of rank), I suggest following in your ancestor's footsteps and joining the Marines. The don't call it "The Few. The Proud. The Marines." for nothing.
If you want to pick up excellent skills that translate well into later civilian life, I would suggest the Air Force first and Navy second. Both are heavy with high tech specialities that make transition back into civilian life with a good career a real possibility.
A word of warning on the National Guard...with numerous "low intensity" conflicts a strong likelihood in the foreseeable future a real possiblity...getting activiated from the Guard is a real possibilty...including overseas duty.
My fully biased opinion is that some manner of national service (Military, Peace Corps, Americorps, etc) should be mandatory for those graduating from high school...gives you a much broader perspective on life and the big, wide world we live in.
~ Old One
PS - At 40, I am considering rejoining the National Guard as a Reserve Officer

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